Winch brake assembly

ABSTRACT

A winch for logging or towing applications including a power train having a plurality of clutches for regulating rotation of a cable drum, a gear clutch providing a positive connection or disconnection between the power train and the cable drum and brake means adapted to produce a limited drag upon the cable drum when the gear clutch is disconnected to prevent rotation of the cable drum except under the influence of external force.

United States Patent [1 1 Wineburner Dec. 10, 1974 1 WINCH BRAKEASSEMBLY [75] Inventor: Ronald E. Winebumer, Pekin, 111.

[73] Assignee: Caterpillar Tractor Co., Peoria, 111.

[22] Filed: June 8, 1973 [21] App]. No.: 368,232

[52] US. Cl. 254/150 R, 254/187 R, 254/175.7 [51] Int. Cl Clld 7/00 [58]Field of Search 254/l75.7, 186 R, 184, 254/185 R, 185 B, 187R,181,179,150,

192/18 A, 17 A, 12 C [56] References Cited UNITED STATES PATENTS1,099,901 6/1914 Baughman et a1. 254/185 B 3,064,946 11/1962 Nojima254/187 X 3,107,899 10/1963 Henneman 254/187 12/1965 Grall et al 254/185X 7/1970 Christison 254/186 X Primary Examiner-Richard A. SchacherAssistant Examiner-James M. Slattery Attorney, Agent, or Firm--Phiilips,Moore, Weissenberger Lempio & Strabala 57 ABSTRACT A winch for loggingor towing applications including a power train having a plurality ofclutches for regulating rotation of a cable drum, a gear clutchproviding a positive connection or disconnection between the power trainand the cable drum and brake means adapted to produce a limited dragupon the cable drum when the gear clutch is disconnected to preventrotation of the cable drum except under the influence of external force.

3 Clainis, 3 Drawing Figures WINCH BRAKE ASSEMBLY BACKGROUND OF THEINVENTION The present invention relates to a winch employable forexample in towing or logging applications. More particularly, theinvention relates to such a winch having a gear clutch for completelydisengaging the cable drum from the winch power train together withbrake means for limiting free-wheeling rotation of the winch drum.

Winches of the type contemplated by the present invention are availablein numerous configurations wherein a plurality of clutches and/or brakesis provided in a power train for the winch to regulate rotation of acable drum. Within such an arrangement, it is desirable to be able tocompletely uncouple the cable drum from the power train, for example, topermit manual unreeling of cable from the drum. However, it has beenfound that the cable drum may continue in rotation even when there is noexternal force being applied to the cable. This has been found to oftenresult in undesirable loosening and tangling of the cable.

SUMMARY OF THE PRESENT INVENTION Accordingly, it is an object of thepresent invention to provide a winch unit including means tosubstantially uncouple'the cable drum from the winch power train tofacilitate free-wheeling operation of the cable drum while providingautomatically operable brake means to provide selectively limited dragupon the cable drum during free-wheeling operation.

Additional objects and advantages of the present invention are madeapparent in the following description having reference to theaccompanying drawings.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation view of a logskidder vehicle with a towing or logging winch including a freewheelingcontrol mechanism according to the present invention.

FIG. 2 is a schematic representation of the cable DESCRIPTION OF THEPREFERRED EMBODIMENT A winch constructed to the present invention may beadapted for towing or logging applications such as in the log skiddervehicle of FIG. I. Thevehicle of FIG.

1 includes a prime mover or engine as illustrated in phantom at 12. Toadapt the vehicle for logging operations, it may include a bulldozermounted on one end of the vehicle for movement between a raised positionillustrated in solid lines at 13 and a lowered position illustrated inphantom at 13. To adapt the vehicle for towing operations, it includesan arch arranged upon the other end of the vehicleas illustrated at 14and a winch illustrated at 16 and constructed according to the presentinvention. Construction and operation of the winch 16 is described ingreater detail below having reference to the other figures.

prise a standard power take-off from the prime mover 12 of the vehiclein FIG. 1, for example. The input shaft 21 is coupled by means ofmeshing transfer gears 22 and 23 with an input shaft 24 for a normallydisengaged friction clutch 26. An output shaft 27 for the clutch 26 iscoupled with a clutch output gear 28 which is secured for rotation witha transfer gear 29. The clutch output gear 28 meshes with a brake gear31 while a normally engaged friction brake 32 is operable to secure thegear 31 against rotation. The components described above comprise anintermediate portion of the winch drive train between the input shaft 21and an output portion, the output portion being partially illustrated ingreater detail by FIG. 3.

The output portion of the winch drive train includes a transfer gear 33arranged in meshing engagement with the gear 29. The gear 33 is mountedupon an input shaft 34 for a bevel gear assembly 36 having bevel gear 37and 38 arranged in meshing engagement. A winch drum shaft 39 provides anoutput for the bevel assembly 36 and a winch drum 41 is arranged forrotation upon the shaft 39 by means of bearings 42 and 43.

In one mode of operation for such a winch unit, the brake 32 may bedisengaged and the clutch 26 simultaneously engaged to rotate the cabledrum in one direction. Conversely, the clutch 26 may be disengaged andthe brake 32 engaged under selective pressure to regulate unreeling ofthe cable drum, for example, under the influence of external forceacting upon the cable.

The present invention particularly contemplates freewheeling controlmeans 44 which permit free-wheeling operation of the cable drum 41 freefrom excessive drag developed by the various portions of the winch drivetrain. Theinvention also contemplates the freewheeling control means 44as including brake means automatically operable to develop a selectivelylimited drag upon the cable drum 41 during free-wheeling operation ofthe cable drum to prevent undesirable loosening or snarling of thecable.

The free-wheeling control assembly of the present invention may be bestseen by having reference to FIG. 3.

The free-wheeling control unit 44 includes a gear clutch 45 which isnormally engaged to provide a coupling between the winch drum shaft 39and the cable drum 41 while being selectively disengageable to permitfree-wheeling of the cable drum.

The clutch 45 includes a drive member 46 and a driven member 47 whichare normally engaged by action of a spring 48. The drive member 46 issupported on the shaft 39 by a sliding spline arrangement 49. The drivenmember 47 is supported relative to the shaft 39 by an adapter 51 andbearing means 52 while being secured to the winch drum 41 by bolts suchas that indicated at 53.

To permit free-wheeling rotation of the cable drum 4], fluid pressure isadmitted into a passage 54 and flows through additional passages 56, 57,58 and 59 formed by various portions of the cable drum assembly to anactuating chamber 61 for the clutch 45. As fluid pressure increases inthe chamber 61 which is formed by the drivemember 46 and a seal adapter62, the drive member 46 is shifted leftwardly against spring 48 tocompletely separate the gear faces on clutch members 46 and 47. Whenthedrive member 46 is completely uncoupled from the driven member 47,the winch drum 41 may be freely rotated to permit unreeling of the cable63 from the cable drum with minimum effort.

To prevent loose or tangled cable because of excessive rotation of thedrum 41 during free-wheeling operation, selectively limited brakingaction is provided by a friction plunger 64 which is hydraulically urgedinto rubbing engagement against a rotation surface 66 of the drivenmember 47. Frictional force supplied by the plunger 64 is adjustable bychanging the load of a spring 67 which normally urges the brake orplunger 64 out of engagement with the member 47.

Engagement of the plunger 64 against the surface 66 is hydraulicallyinitiated simultaneously with disengagement of the clutch 45. Hydraulicfluid under pressure from the passage 56 penetrates a bearing 68 and iscommunicated from a chamber 69 into a conduit 71 leading to an actuatingchamber 72 adjacent a piston 73 coupled to the plunger 64.

Accordingly, as the clutch 45 is disengaged by hydraulic fluid in theactuating chamber 61 to permit free-wheeling operation of the cable drum41, the frictional plunger is urged leftwardly as viewed in FIG. 3 toprovide a selectively limited drag upon the driven clutch member 47. Theplunger 64 is, of course, immediately withdrawn from frictionalengagement with the member 47 once actuating fluid is withdrawn from theclutch 45. It may be noted that the free-wheeling control unit of thepresent invention substantially eliminates unnecessary frictional wearduring operation of the winch unit. The limited frictional engagementdeveloped between the plunger 64 and the driven member 47 arises only asnecessary during free-wheeling operation and accordingly is limited induration, thus contributing to more reliable and longer life operationof the winch unit.

What is claimed is:

l. A winch unit comprising a power input member,

a power train including at least one clutch coupled to the input member.the power train including an output shaft,

a cable drum,

a normally engaged gear clutch arranged between the output shaft and thecable drum, the normally engaged clutch being disengageable to permitfreewheeling rotation of the cable drum, and

brake means simultaneously actuatable along with the normally engagedclutch to produce limited drag on the cable drum and prevent excessiverotation of the cable drum during free-wheeling operation,

the normally engaged clutch and the brake means being hydraulicallyoperable by fluid pressure introduced into the respective actuatingchambers in communication with each other.

2. A winch unit comprising a power input member,

a power train including at least one clutch coupled to the input member,the power train including an output shaft,

a cable drum,

a normally engaged gear clutch arranged between the output shaft and thecable drum, the normally engaged clutch being disengageable to permitfreewheeling rotation of the cable drum, and

brake means simultaneously actuatable along with the normally engagedclutch to produce limited drag on the cable drum and prevent excessiverotation of the cable drum during free-wheeling operation,

the brake means including a frictional plunger urged out of effectiveengagement with the cable drum byresilient means and an actuatingchamber for receiving hydraulic fluid simultaneously with disengagementof the normally engaged clutch to urge the plunger into frictionalengagement with the cable drum. 3. The winch of claim 2 wherein thenormally engaged clutch also includes a hydraulic actuating chamber ineffective communication with the actuating chamber for the brake means.v

1. A winch unit comprising a power input member, a power train includingat least one clutch coupled to the input member, the power trainincluding an output shaft, a cable drum, a normally engaged gear clutcharranged between the output shaft and the cable drum, the normallyengaged clutch being disengageable to permit free-wheeling rotation ofthe cable drum, and brake means simultaneously actuatable along with thenormally engaged clutch to produce limited drag on the cable drum andprevent excessive rotation of the cable drum during freewheelingoperation, the normally engaged clutch and the brake means beinghydraulically operable by fluid pressure introduced into the respectiveactuating chambers in communication with each other.
 2. A winch unitcomprising a power input member, a power train including at least oneclutch coupled to the input member, the power train including an outputshaft, a cable drum, a normally engaged gear clutch arranged between theoutput shaft and the cable drum, the normally engaged clutch beingdisengageable to permit free-wheeling rotation of the cable drum, andbrake means simultaneously actuatable along with the normally engagedclutch to produce limited drag on the cable drum and prevent excessiverotation of the cable drum during free-wheeling operation, the brakemeans including a frictional plunger urged out of effective engagementwith the cable drum by resilient means and an actuating chamber forreceiving hydraulic fluid simultaneously with disengagement of thenormally engaged clutch to urge the plunger into frictional engagementwith the cable drum.
 3. The winch of claim 2 wherein the normallyengaged clutch also includes a hydraulic actuating chamber in effectivecommunication with the actuating chamber for the brake means.